1. Field
Exemplary embodiments of the present invention relate to a test device and a test system of a semiconductor device and a test method for testing a semiconductor device.
2. Description of the Related Art
During a production process of a semiconductor device, a probe test is performed to determine whether a memory cell of a semiconductor device on a wafer performs a read operation or a write operation correctly. The probe test determines a malfunction of the semiconductor device by coupling a probe of a probe card to each pad of the semiconductor device on a wafer and inputting and outputting a power voltage and a signal.
However, it may be requested for a correct probe test to electrically couple the probe of the probe card to each pad of the semiconductor, for inputting and outputting the power voltage and the signal of the semiconductor device. Thus, it may be important to analyze an electrical coupling between the probe of the probe card and each pad of the semiconductor device.
In case of a conventional probe test for determining whether a probe of a probe card is coupled to a pad of a semiconductor device or not, a test current flows through the probe coupled to the pad of the semiconductor, and a voltage that is applied to the pad of the semiconductor device is measured in response to the test current. Here, a predetermined voltage level is measured if the probe is coupled to the pad of the semiconductor device, and a predetermined voltage is not measured if the probe is not coupled to the pad of the semiconductor device. In other words, if the probe is not coupled to the pad of the semiconductor device, a measured voltage level has a lowest value of a voltage measurement range.
Meanwhile, a plurality of probes is used in one channel of a test device because of a limited number of channels of a test device during a probe test. Thus, it is requested to analyze an electrical coupling between the plurality of probes and a plurality of interface pads of the semiconductor device before the probe test is performed.
In a case of conventional probe test method, after a test current flows to a plurality of probes coupled to each pad of the semiconductor device, an electrical coupling is analyzed between the plurality of probes and each pad of the semiconductor by using a voltage outputted in response to the test current. However, because a plurality of probes is coupled to one channel of the test device in parallel, a voltage is measured although one of the plurality of probes is coupled to a pad of a semiconductor device. The voltage may be maintained constantly irrespective of a number of the probes that is coupled to the pad. Furthermore, the voltage is measured irrespective of a coupling strength state between the probes and the pad. Thus, it may be difficult to analyze whether each of probes is coupled to the pad or not and analyze a coupling strength state between each of probes and the pad.